Page 377 of 508

Black plate (33,1)Chevrolet Avalanche Owner Manual - 2012
Vehicle Care 10-33
Starter Switch Check
{WARNING
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle.
2. Firmly apply both the parking brake and the regular brake.
See Parking Brake on
page 9‑45.
Do not use the accelerator
pedal, and be ready to turn off
the engine immediately if it
starts. 3. Try to start the engine in each
gear. The vehicle should start
only in P (Park) or N (Neutral).
If the vehicle starts in any other
position, contact your dealer for
service.
Automatic Transmission
Shift Lock Control
Function Check
{WARNING
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle. It should be
parked on a level surface. 2. Firmly apply the parking brake.
See Parking Brake on
page 9‑45.
Be ready to apply the regular
brake immediately if the vehicle
begins to move.
3. With the engine off, turn the ignition on, but do not start the
engine. Without applying the
regular brake, try to move the
shift lever out of P (Park) with
normal effort. If the shift lever
moves out of P (Park), contact
your dealer for service.
Page 378 of 508

Black plate (34,1)Chevrolet Avalanche Owner Manual - 2012
10-34 Vehicle Care
Ignition Transmission
Lock Check
While parked, and with the parking
brake set, try to turn the ignition to
LOCK/OFF in each shift lever
position.
.The ignition should turn to
LOCK/OFF only when the shift
lever is in P (Park).
.The ignition key should come
out only in LOCK/OFF.
Contact your dealer if service is
required.
Park Brake and P (Park)
Mechanism Check
{WARNING
When you are doing this check,
the vehicle could begin to move.
You or others could be injured
and property could be damaged.
Make sure there is room in front
of the vehicle in case it begins to
roll. Be ready to apply the regular
brake at once should the vehicle
begin to move. Park on a fairly steep hill, with the
vehicle facing downhill. Keeping
your foot on the regular brake, set
the parking brake.
.To check the parking brake's
holding ability: With the engine
running and the transmission in
N (Neutral), slowly remove foot
pressure from the regular brake
pedal. Do this until the vehicle is
held by the parking brake only.
.To check the P (Park)
mechanism's holding ability:
With the engine running, shift to
P (Park). Then release the
parking brake followed by the
regular brake.
Contact your dealer if service is
required.
Page 379 of 508

Black plate (35,1)Chevrolet Avalanche Owner Manual - 2012
Vehicle Care 10-35
Wiper Blade Replacement
Windshield wiper blades should be
inspected for wear or cracking. See
Maintenance Schedule on
page 11‑3.
Replacement blades come in
different types and are removed in
different ways.
To replace the wiper blade
assembly:
1. Pull the windshield wiper armconnector away from the
windshield.
2. Squeeze the grooved areas on
each side of the blade, and
rotate the blade assembly away
from the arm connector.
3. Install the new blade onto thearm connector and make sure
the grooved areas are fully set in
the locked position.
For the proper type and size, see
Maintenance Replacement Parts on
page 11‑14.
Glass Replacement
If the windshield or front side
glass must be replaced, see your
dealer to determine the correct
replacement glass.
Headlamp Aiming
The vehicle has a visual optical
headlamp aiming system. The aim
of the headlamps has been preset
at the factory and should need no
further adjustment.
However, if the vehicle is damaged
in a crash, the aim of the headlamps
may be affected and adjustment
may be necessary.
If oncoming vehicles flash their high
beams at you, this may mean the
vertical aim of the headlamps needs
to be adjusted.
It is recommended that the vehicle
be taken to your dealer for service if
the headlamps need to be adjusted.
It is possible, however, to re-aim the
headlamps as described.
Page 380 of 508

Black plate (36,1)Chevrolet Avalanche Owner Manual - 2012
10-36 Vehicle Care
The vehicle should:
.Be placed so the headlamps
are 7.6 m (25 ft) from a
light‐colored wall.
.Have all four tires on a level
surface which is level all the
way to the wall.
.Be placed so it is perpendicular
to the wall.
.Not have any snow, ice, or mud
on it.
.Be fully assembled and all other
work stopped while headlamp
aiming is being performed.
.Be loaded with a full tank of
fuel and one person or 75 kg
(160 lbs) sitting on the
driver seat.
.Have the tires properly inflated.
.Have the spare tire in its proper
location in the vehicle.Headlamp aiming is done with the
vehicle's low-beam headlamps.
The high-beam headlamps will be
correctly aimed if the low-beam
headlamps are aimed properly.
To adjust the vertical aim:
1. Open the hood. See
Hood on
page 10‑52. Locate the aim dot on the lens of the low‐beam headlamp. 3. Record the distance from the
ground to the aim dot on the
low‐beam headlamp.
4. At a wall, measure from the
ground upward (A) to the
recorded distance from
Step 3 and mark it.
5. Draw or tape a horizontal line (B) on the wall the width of the
vehicle at the height of the mark
in Step 4.
Page 381 of 508

Black plate (37,1)Chevrolet Avalanche Owner Manual - 2012
Vehicle Care 10-37
Notice:Do not cover a headlamp
to improve beam cut-off when
aiming. Covering a headlamp may
cause excessive heat build-up
which may cause damage to the
headlamp.
6. Turn on the low-beam
headlamps and place a piece of
cardboard or equivalent in front
of the headlamp not being
adjusted. This allows only the
beam of light from the headlamp
being adjusted to be seen on the
flat surface.
7. Locate the vertical headlampaiming screws, which are under
the hood near each headlamp
assembly.
The adjustment screw can be
turned with an E8 Torx
®socket.
8. Turn the vertical aiming screw until the headlamp beam is
aimed to the horizontal tape
line. Turn it clockwise or
counterclockwise to raise or
lower the angle of the beam.
9. Make sure that the light from theheadlamp is positioned at the
bottom edge of the horizontal
tape line. The lamp on the
left (A) shows the correct
headlamp aim. The lamp on the
right (B) shows the incorrect
headlamp aim.
10. Repeat Steps 7 through 9 for the opposite headlamp.
Page 382 of 508
Black plate (38,1)Chevrolet Avalanche Owner Manual - 2012
10-38 Vehicle Care
Bulb Replacement
For the proper type of replacement
bulbs, seeReplacement Bulbs on
page 10‑39.
For any bulb‐changing procedure
not listed in this section, contact
your dealer.
Halogen Bulbs
{WARNING
Halogen bulbs have pressurized
gas inside and can burst if you
drop or scratch the bulb. You or
others could be injured. Be sure
to read and follow the instructions
on the bulb package.
Taillamps, Turn Signal,
Sidemarker, Stoplamps,
and Back-Up Lamps
A. Back-up Lamp
B. Stoplamp/Turn Signal/Taillamp
C. Sidemarker Lamp To replace one of these bulbs, do
the following:
1. Open the tailgate. See
Tailgate
on page 2‑16 for more
information.
2. Remove the two screws from the taillamp assembly.
3. Pull the taillamp assembly rearward until you disengage the
outer pins on the taillamp
assembly from the vehicle.
Page 383 of 508

Black plate (39,1)Chevrolet Avalanche Owner Manual - 2012
Vehicle Care 10-39
4. Turn the bulb socketcounterclockwise to remove it
from the taillamp assembly.
5. Pull the old bulb straight out from the bulb socket.
6. Press a new bulb into the bulb socket and insert the bulb socket
into the taillamp assembly. Turn
the bulb socket clockwise into
the taillamp assembly until it
clicks.
7. Reinstall the taillamp assembly making sure to line up the pins
with the vehicle.License Plate Lamp
To replace one of these bulbs:
1. Reach under the rear bumper for
the bulb socket. Turn the bulb
socket counterclockwise and pull
the bulb socket out of the lamp
assembly.
2. Pull the bulb straight out of the socket.
3. Install the new bulb into the socket.
4. Reinstall the bulb socket by turning it clockwise into the lamp
assembly.
Replacement Bulbs
Exterior Lamp Bulb
Number
Back-up Lamp 7441
License
Plate Lamp 168
Rear Turn Signal
Lamp, Taillamp,
and Stoplamp 3057K
Sidemarker Lamp 194LL
For replacement bulbs not listed
here, contact your dealer.
Page 384 of 508

Black plate (40,1)Chevrolet Avalanche Owner Manual - 2012
10-40 Vehicle Care
Electrical System
Electrical System
Overload
The vehicle has fuses and circuit
breakers to protect against an
electrical system overload.
When the current electrical load is
too heavy, the circuit breaker opens
and closes, protecting the circuit
until the current load returns to
normal or the problem is fixed. This
greatly reduces the chance of circuit
overload and fire caused by
electrical problems.
Fuses and circuit breakers protect
power devices in the vehicle.Replace a bad fuse with a new one
of the identical size and rating.
If there is a problem on the road and
a fuse needs to be replaced, the
same amperage fuse can be
borrowed. Choose some feature of
the vehicle that is not needed to use
and replace it as soon as possible.
Headlamp Wiring
An electrical overload may cause
the lamps to go on and off, or in
some cases to remain off. Have the
headlamp wiring checked right away
if the lamps go on and off or
remain off.
Windshield Wipers
If the wiper motor overheats due to
heavy snow or ice, the windshield
wipers will stop until the motor cools
and will then restart.
Although the circuit is protected
from electrical overload, overload
due to heavy snow or ice may
cause wiper linkage damage.
Always clear ice and heavy snow
from the windshield before using the
windshield wipers.
If the overload is caused by an
electrical problem and not snow or
ice, be sure to get it fixed.